The inventive concept relates to semiconductor devices. More particularly, the inventive concept relates to variable resistance memory devices and to methods of manufacturing the same.
Semiconductor devices may be classified as memory devices or logic devices. Memory devices store data. Generally, semiconductor memory devices may be classified as volatile memory devices or nonvolatile memory devices. Volatile memory devices lose their stored data when the power supplied thereto is interrupted. Volatile memory devices include dynamic random access memory (DRAM) devices, and static random access memory (SRAM) devices. On the other hand, nonvolatile memory devices retain their stored data even when the power supplied thereto is interrupted. Nonvolatile memory devices include programmable read only memory (PROM) devices, erasable PROMs, electrically erasable PROMs (EPROMs), and flash memory devices.
Also, next generation semiconductor memory devices such as ferroelectric RAMs (FRAMs), magnetic RAMs (MRAMs), and phase change RAMs (PRAM), are being developed to offer higher performance while consuming lower amounts of power. Characteristically, materials constituting those next generation semiconductor memory devices have different resistance values depending on the values of the current and voltage supplied thereto, and maintain their resistance values even when the current or voltage supply is interrupted.